Re: [dtp-dev] bug#149611 - Database Version is not flexible ...

[Anil T Samuel <anil.samuel@xxxxxxxxxx>]

Rob

I like to comment on the current impl of JDBCConnection class.

The JDBCConnection class's constructor is as below

       public JDBCConnection(IConnectionProfile profile, Class 
factoryClass) {
               super(profile, factoryClass);
               open();
       }

If I have a subclass as below
class OracleJDBCConnection extends JDBCConnection{
   String providerName = null;
   public OracleJDBCConnection(){
      super();
      providerName = "Oracle Database";
   }

  @Override
  public String getProviderName(){
      return providerName;
  }
}

The super() flows into open() in superclass which calls 
getProviderName() along the line; but the subclass havenot populated 
providerName value yet, which results a NPE. This results the label 
provider to fail in the contentNavigator context.

The call stack copied from Eclipse is as below
OracleJDBCConnection.getProviderName() line: 50   
OracleJDBCConnection(VersionProviderConnection).updateServerVersion(Properties) 
line: 174   
OracleJDBCConnection(VersionProviderConnection).updateVersionCache() 
line: 86   
OracleJDBCConnection(DriverConnectionBase).internalCreateConnection() 
line: 112   
OracleJDBCConnection(DriverConnectionBase).open() line: 53   
OracleJDBCConnection(JDBCConnection).<init>(IConnectionProfile, Class) 
line: 48   
OracleJDBCConnection.<init>(IConnectionProfile, Class) line: 20   
OracleJDBCConnectionFactory.createConnection(IConnectionProfile) line: 
15   
ConnectionFactoryProvider.createConnection(IConnectionProfile, String, 
String) line: 85   
ConnectionFactoryProvider.createConnection(IConnectionProfile) line: 69   
ConnectionProfile.createConnection(String) line: 304   
ConnectionInfoImpl.<init>(IConnectionProfile, Class) line: 622   
SQMConnectionFactory(ConnectionFactory).createConnection(IConnectionProfile) 
line: 36   
SQMConnectionFactory.createConnection(IConnectionProfile) line: 45   
ConnectionFactoryAdapterProvider.createConnection(IConnectionProfile) 
line: 79   
CreateConnectionJob.run(IProgressMonitor) line: 55   
Worker.run() line: 58   

So my suggestion is to move out the open() from JDBCConnection(..).

Regards
Anthos

rcernich@xxxxxxxxxx wrote:
> Hey Anthos,
>
> Could you please provide specific examples where you cannot satisfactorily
> override the default behavior?  I would like to resolve any shortcomings in
> the API that restrict specialization (as this is a framework, it is
> important that the behavior can be customized, within limits of course).
>
> See below for comments on the specific usages you listed.
>
> Best regards,
> Rob
>
> dtp-dev-bounces@xxxxxxxxxxx wrote on 07/06/2006 04:13:40 PM:
>
>   
> > The static method Version.valueOf(..) is in used in few places in the
> > core code, which makes it difficult to override the Version class to
> > handle vendor specific way.
> >     
>
> You can provide whatever data is required to the valueOf() method.  This
> may require formatting your input prior to invoking valueOf().  You can
> always use the constructor directly, which specifies individual parameters
> for major, minor, release, and build components.
>
>
>   
> > projects/opensource/eclipse-src/org.eclipse.datatools.connectivity/
> > plugins/org.eclipse.datatools.connectivity/src/org/eclipse/datatools/
> > connectivity/VersionProviderConnection.java:149:
> > Version oldTechVersion = Version.valueOf(props.getProperty(
> >     
>
> Version information is stored in the properties using Version.toString()
> (Version.valueOf(aVersion.toString()).equals(aVersion) == true).
>
>   
> > projects/opensource/eclipse-src/org.eclipse.datatools.connectivity/
> > plugins/org.eclipse.datatools.connectivity/src/org/eclipse/datatools/
> > connectivity/VersionProviderConnection.java:175:             Version
> > oldServerVersion = Version.valueOf(props.getProperty(
> >     
>
> Same as preceding comment.
>
>
>   
> > projects/opensource/eclipse-src/org.eclipse.datatools.connectivity/
> > plugins/org.eclipse.datatools.connectivity.db.generic/src/org/eclipse/
> > datatools/connectivity/db/generic/JDBCConnection.java:
> > 152:                          mServerVersion = Version.valueOf
> > (versionString);
> >     
>
> Assumes DatabaseMetaData.getDatabaseProductVersion() is of the form
> <int>.<int>.<int>.<string>; not sure what the JDBC specification says about
> the string returned by this method.  However, since extenders have the
> ability to override the IServerVersionProvider methods on JDBCConnection,
> they can easily tailor the implementation of these to match the information
> returned by their server (e.g. by reformatting the string or by
> instantiating a version object directly using its constructor).
>
>
>   
> > projects/opensource/eclipse-src/org.eclipse.datatools.connectivity/
> > plugins/org.eclipse.datatools.connectivity.oda.profile/src/org/
> > eclipse/datatools/connectivity/oda/profile/OdaConnectionWrapper.java:
> > 144:            return Version.valueOf
> > ( m_odaMetadataHelper.getDataSourceProductVersion() );
> >     
>
> I assume this is internally consistent with ODA (i.e. that
> getDataSourceProductVersion() returns a compatible string).
>
>
>   
> > projects/opensource/eclipse-src/org.eclipse.datatools.connectivity/
> > plugins/org.eclipse.datatools.connectivity.oda.profile/src/org/
> > eclipse/datatools/connectivity/oda/profile/OdaConnectionWrapper.java:
> > 179:        return Version.valueOf( Constants.ODA_COMPONENT_VERSION );
> >     
>
> Same as preceding comment.
>
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